1. Field of the Invention
The invention relates to domed building structures and, in particular, to a domed building structure having a framework of spars each extending between a respective pair of points on a notional envelope of the framework assembled from a plurality of individual panels.
2. Background Information
Domed building structures of this general type are disclosed, for example, in U.S. Pat. Nos. 4,285,174; 4,665,664; 4,686,801 and 5,170,599, and in European Patent Application No. EP-0773331A, to which reference should be had.
European Patent Application 0773331 discloses a domed building structure comprising a plurality of substantially concentric parts disposed one above the other and including a central upper apex part and one or more lower parts each forming a respective frustum adjoining the part immediately above, and wherein each said frustum is formed of a plurality of straight-edged panels, each extending from the upper inner edge of the frustum to the lower outer edge, each junction between panel edges at each said upper inner edge of the or each frustum being coincident with a respective junction between panel edges at the adjoining edge of the frustum or central upper part immediately above, and at least one said frustum comprising both four-sided and triangular panels, with each triangular panel having an apex coincident with a junction between four-sided panels in the upper inner edge of the respective frustum, and having a base forming a respective part of the lower outer edge of the respective frustum.
GB-2339806 discloses such a structure in which, additionally, each said four sided panel is trapezoidal, with the shorter of its parallel edges lying in the lower, outer, edge of the frustum and the longer of its parallel edges lying in the upper, inner edge of the frustum.
Known domed building structures of this type are generally substantially circular in plan and exhibit, from a microscopic viewpoint, substantial rotational symmetry about a vertical central axis. This form has the advantages of strength and stability, but there are, of course, circumstances in which a circular ground plan, for example is not ideal from other considerations, for example where it is desired that the dome should encompass a rectangular, or otherwise non-circular sports pitch, or where it is desired to make the most efficient use, in terms of utilisation of plan area, of a generally rectangular site, or to fit a plurality of similar structures close together on the ground without waste of space.